module.exports = frob

/**
 * Returns Frobenius norm of a mat2
 *
 * @alias mat2.frob
 * @param {mat2} a the matrix to calculate Frobenius norm of
 * @returns {Number} Frobenius norm
 */
function frob(a) {
  return Math.sqrt(
    Math.pow(a[0], 2) +
    Math.pow(a[1], 2) +
    Math.pow(a[2], 2) +
    Math.pow(a[3], 2)
  )
}